<nav class="navbar navbar-default" role="navigation">
  <div class="container">
    



<div class="navbar-header">
          <button type="button" class="navbar-left navbar-toggle collapsed " data-toggle="collapse" data-target="#navbar" aria-expanded="false" aria-controls="navbar">
            <span class="sr-only">Toggle navigation</span>
            <span class="icon-bar"></span><!-- 三个带有.icon-bar 的 <span> 创建所谓的汉堡按钮 -->
            <span class="icon-bar"></span>
            <span class="icon-bar"></span>
          </button>
          <a class="navbar-brand" href="/">Log</a><!-- navbar-brand让文本看起来更大一号 -->
    </div>
	
	




<div id="navbar" class="collapse navbar-collapse pull-right"><!-- 给导航栏添加响应式，包裹在带有.collapse、.navbar-collapse  -->
          <ul class="nav navbar-nav" id="myTab">
          <!--nav navbar-nav 导航栏添加链接-->
            <!-- <li class="active"><a href="/"><span class="glyphicon glyphicon-home"></span> 首页</a></li>
            -->
            <li><%= link_to("登入", new_session_path) %> </li>
          </ul>

</div>

  </div>
</nav>


